Electric switch



- May 5, 1931. G. H. ELWELL 1 I 0 ELECTRIC SWITCH Filed 001;. 10, 1927 Patented May 5, 1931 UNITED STATES FATENT oFFicE I GEORGE HENRY ELWELL, OF NEW HAVEN, CONNECTICUT, ASSIGNOR TO THE GREIST MANUFACTURING COMPANY, OF NEW HAVEN, CONNECTICUT, A CORPORATION OF CONNECTICUT ELECTRIC SWITCH Application filed October 10, 1927. Serial No. 225,196.

The invention relates to improvements in electric switches and especially to that type of switches providing "a means for instantaneous making and breaking of contact to close and open the electrical circuit without sparking. The art discloses various constructions of this type of switch, but so far as the applicant is aware no switch of such a type has been previously introduced wherein the reciprocating operating member controls a contacting member movable in a plane at right angles thereto and into direct engagement with the center contact presented by the ordinary incandescent lamp bulb within the screw-shell contact, and the objects therefore of the invention are to provide an electrical switch having a plunger contacting element movable axially for direct engagement with a center contact provided by an incandescent lamp; to provide a contacting element of that character with an instantaneous making and breaking movement; and to provide such a contacting element with binding-post in direct alignment therewith, the center line of both being the axis of the lamp socket.

While the improved electric switch is adapted for use in connection with any electrical device the following is the description of an embodiment of the invention in connection with anelectric lamp socket the constru'ction of which, within the scope of what hereinafter is claimed, may be varied without departing from the spirit or modifying any of the advantages of the invention.

Reference being had to the accompanying drawing (one sheet) Figure 1 is an upright exterior elevation of an electric lamp socket provided with the improved electric switch; Figure 2 is an upright elevation of the same socket in 'a difierent rotary position and partly in cross-section to illustrate an interior part; Figure 3 is an upright exterior elevation of the same socket in the same position 7 as the next preceding figure; Figure 4 is an upright elevation of the same socket in the position illustrated in Figure 1, but partly in cross-section to illustrate an interior part; Figure 5 illustrates detail parts in perspective; and Figure 6 is a sectional perspective view of detail.

Referrin more particularly to the drawing, in whic 1 similar parts are similarly numbered, the body of insulation 1 is provided with the peripheral opening 2, as illustrated by Figure 1, which opening extends entirely through the body to provide the 'tranverse cavity 3 as illustrated by the Figure 2. A center cavity 4 communicates with the transverse cavity 3 and is continued through the line of axis of the socket at a reduced diameter by the bore 5. Seated within the bore 5 is the tubular sleeve 6 having an annular flange 7 resting within the cavity 4 upon the annular shoulder terminating that cavity, the sleeve being internally threaded at its free end. The plunger con tact element 8 is movably mounted at one extremity within the unthreaded portion of the sleeve '6 and is provided with a later'al'projection 9, the remaining portion of the plunger 8 having a reduced diameter and being provided with an elongated longitudinal slot 10, as best illustrated by Figure 5-. Ii movable cap 11 is mounted upon the extrem ity of the slotted portion of the plunger 8 and limited in its relative movement thereon by means of the inwardly extending projections 12, each adapted to engage for sliding movement within opposite sides of the slot 10. The length of the plunger 8 is such that the cap 11 is movably confined within a. central perforation 13 provided by the washer of insulation 14, as best illustrated by Figures 2 and 4. Coiled wire springs 15 and '16 are mounted upon the reduced portion of the plunger 8, an end of one of the coils resting I against a shoulder formed by reducing the diameter of the plunger, and an end of the other coil resting against, the annular edge of the cap '11. v The reciprocating operating member 17,is preferably a one-piece construction as best illustrated by Figure 5 having means for attaching the push elements 18 and 19 attached to its extremities 20 and 21, respectively. The floor 22 of the member 17 is partially cutaway to form the recess :28 and the spaced notches 2e and 25 therein. The inclined rigid arm 26 is an integral part ofthe floor 22 and is folded at right angles thereto so as to overhang the full length of the recess 23.

The operating member 17 and the plunger 8 are assembled each within their respective cavities simultaneously in order that the inclined arm 26 may be inserted within the slot 10 between the coiled springs 15 and 16. It is obvious that when so assembled the member 1! may be moved in either direction to increase the tension of one or the other spring according to the position of the inclined arm 26. The spring 16, for instance, being thus placed under tension, as illustrated by Figure 2, the plunger element 8 as soon as the notch 24: registers with the projection 9 instantaneously assumes the open circuit position, the

, contact with the incandescent lamp center contact 27 having thereby become broken. By placing the spring 15 under tension with a reversed movement of the operating member 17 the plunger element 8. as soon as the notch 25 registers with the projection 9, instantaneously assumes the closed circuit position as illustrated by Figure 4e, it thereby having been plunged against the incandescent lamp center contact 27. it will be noticed that, in the operation of the plunger element 8, the lateral projection 9 alternately engages first one and then the other side surface of that portion of the floor 22 within the recess 23 and lying between the spaced notches 24c and 25, and that it is this alternate engagement that retards the movement in either direction of the plunger element 8 until a registration is had between the projection 9 and one of the notches. Of course there is nothing to prevent the lateral'projection 9 being carried by its floor-engaging position in the movement of the plunger element to connect with the incandescent lamp center contact 27. Because of this fact the spring-pressed cap 11 is made to function to maintain a positive electrical connection even while the spring 16 is being gradually placed under tension preparatory to the breaking of the electrical contact. The spring-pressed cap 11 also functions similarly to allow for the manufacturing tolerance in the making of both lamps and sockets and thus insure at all times and under all circumstances a positive electrical contact. The binding-post screw 28 engages the threaded portion of the interior of the sleeve 6 while the binding-post screw 29 engages in a threaded bore provided by an arm integral with the screw-shell and made the subject of a separate application of even date herewith and filed October 10, 1927, Serial No. 225,191,11ow Patent 1,762,512 of June 10, 1930. A channel 30 provided by the body 1 adjacent to the screw 29 provides direct means for wire connectio therethrough with the screw 29.

lVhat I claim is 1. An electrical switch comprising a supporting base of insulation providing intersecting runways, two reciprocating members, each member intersecting and movable at right angles to the other Within therunways,

and connections between the members adapting one member to instantaneously move the other member in alternate directions.

2. An electric switch comprising a supporting base of insulation providing intersecting runways, a reciprocatingoperating member and a plunger element, each intersecting and movable at right angles to the other within the runways and carrying connections adapting the plunger element to be instantaneously moved in alternate directions by means of the operating member.

3. An electric switch comprising a supporting base of insulation providing intersecting runways, a lon itudinally slotted plunger contact element supporting coiled springs between spaced shoulders provided by the plunger movable in one runway, and a reciprocating operating member movable in the other runway and carrying an inclined arm to travel within the slot and between the springs to cooperate wit-h the springs to exert an alternate spring tension upon the plunger element in opposite directions, and

a retarding means provided by the plunger element and the operating member to hold the plunger element for instantaneous movement upon theffull tensioning of a spring.

l. An'electric switch comprising a supporting base of insulation providing intersecting runways, a longitudinally slotted plunger element movable in one runway, the plunger having an intermediate shoulder and provided at one extremity with a movable cap assembled to the plunger by means of inwardly formed lateral projections provided by the cap and adapted to slide within the slot,

coiled springs supported by the plunger be-' tween the shoulder and the cap, a reciprocating operating member movablein the otherrunway and rigidly carrying an inclined arm adapted to travel within the slot and between the springs to cooperate with the springs to exert an alternate spring tension uponthe plunger element inopposite directions, and a rigid retarding means carried by the plunger element and cooperating with means provided by the operating member to hold the plunger element for instantaneous movement" upon the full tensioning of a sprin 5. An electric switch comprising a supporting base of insulation providing intersecting runways, a longitudinally slotted plunger element movable in one runway and having an intermediate shoulder and a movable cap assembled to the plunger by means of inwardly formed lateral projections provided by the cap and adapted to .slide within the slot, coiled springs surrounding the plunger and supported between the shoulder. and the cap, and a reciprocating operating member movable in the other runway and carrying an inclined rigid arm adapted to travel within the slot and between the springs to cooperate with the springs to exert an alternate spring tension upon the plunger element in opposite directions, and a retarding means comprising a lateral projection provided by the plunger element and spaced notches provided by the operating member, the projection being adapted to register with one or the other of the notches to permit the movement of the plunger upon the tensioning of a spring.

6. An electric switch for an electric lamp socket and comprising a supporting base of insulation providing intersecting runways, a reciprocating operating member and a plunger contact element, each intersecting and movable at right angles to the other Within the runways, connections adapting the member to move the element instantaneously in opposite directions to make and break direct electrical connection with the center contact of an incandescent lamp base held by the lamp socket, and a binding-post within which the plunger contact element is mounted, the center line of the post being the axis of the electric lamp socket.

7. An electric switch for an electric lamp socket and comprising a supporting base of insulation providing intersecting runways, a reciprocating operating member and a plunger contact element, each! intersecting and movable at right angles to the other within the runways, and connections adapting the member to move the element instantaneously in alternate directions, the plunger contact element having a spring-pressed cap yieldingly engageable with the center contact of an incandescent lamp held by the lamp socket.

GEORGE HENRY ELWELL. 

